People are increasingly utilizing portable computing devices to perform various tasks, such as viewing a personal calendar, managing business contacts, checking email messages, taking photos, playing video games, or checking the weather. Many applications on a computing device (e.g., work calendar, personal email, business contacts) enable a user to access confidential information or information that the user would like to protect. At the same time, many other applications on the computing device (e.g., camera, calculator, navigator) provide functions that do not contain or give access to any confidential information that the user would care to protect. Thus, while having an overall password lock may secure access to all data on the computing device, the user may find it inconvenient to always have to unlock the overall device using the password even when accessing applications that do not contain any confidential information.
Further, while the user may want to lend the computing device to others to share applications that do not contain confidential information (e.g., video games, navigation information, photos), the user might feel uncomfortable when there is no way to protect or limit access to applications that may contain confidential information once the overall password is unlocked. Some conventional approaches enable a user to provide different passwords to protect each of a number of different applications or sources of data on the device, but the user might not appreciate having to enter a specific password each time the user wants to access one of these applications or sources.